Reaproveitamento de cinzas de madeira para a produção de cerâmica vermelha e estudo das propriedadesmecânicas e tecnológicas pós sinterização.

Abstract

Many industrial processes are sources of waste, causing almost always the degradation of the environment.One of these residues comes from the burning of wood, necessary for thegeneration of heat in the furnacesof the red ceramic industries. Brazil is one of the biggest explorers of this type of energy source, and it ends up generating a significant amount of ashes. Most of these ashes are disposed of without special care, which can cause damage to the environment and generate risks of contamination in the air in the form of particulate material. Waste recycling is an opportunity to transform an important source of pollution into a source of revenue or, at least, to reduce expenses. The red ceramic industry presents itself as a potential absorber of ash residues, since they can be incorporated into the clay mass in a way that does not harm its physical and mechanical properties, and yet it presents itself as a good alternative for reducing the environmental impact caused. Knowing this, this work aims to study the feasibility of using ashes of cashew wood firewood collected in the oven of a red ceramic industry, aiming at its reuse in the clay masses by means of dry pressing of the sieved powders and sintering in the temperatures of 850 ° C, 950 ° C and 1100 ° C. For this, tests were performed to determine the physical properties (linear shrinkage, water absorption, specific mass, loss of mass on fire and optical microscopy) and to determine the mechanical properties (Rockwell B hardness, axial compression strength and tensile strength diametrical compression). The results showed that the addition of up to 20% by weight of ash to the clay matrix improved the mechanical strength in the diametrical compression, and through the linear shrinkage and water absorption tests, it was found that there was a reduction in porosity due to complete vitrification, generating better packaging of the particles. Therefore, through this work it was proved that it is possible to add to the clay the analyzed percentages of this by-product, thus being able to become an environmentally correct destination for this residue.